Composition useful as an antioxidant for fats and oils



Patented Aug. 19 1952 UNITED STATES PATENTOFFICE v COMPOSITION USEFUL ASAN ANTIOXIDANT FOR FATS AND OILS James E. Magoffin, Kingsport, Tenn.,assignor to Eastman Kodak Company, Rochester, corporation of New JerseyNo Drawing. Application May 5, 1949, V

- Serial No. 91,635

This invention relates to compositions useful as antioxidants for fatsand oils. This applicaknown that the antioxidant action of such phenolicantioxidants can be synergized with acids, e. g. citric acid,orthophosphoric acid, tartaric acid, etc. While these phenoliccompounds, as well as their synergisticcombinations with acids, suchas.citricracid;etcyhave been found to be highly effective in retardingthe oxidative rancidity during storage of fats and oils, they aresubject to the disability in many instances of being only slightlysoluble in the fatty materials to which they are added. In processingsuch fats and oils a considerable percentage of the effective amounts ofthe antioxidants are frequently lost due to this lack of sufficientsolubility. V

I have now found that the dispersion of these antioxidants in fats andoils .can be materially rial to be stabilized, thus enabling one tosecure uniformly dispersed mixtures of the antioxidant in the fattymaterials and more effectively to prevent oxidation with a givenproportion of antioxidant to fat.

According to my invention, one or more ,alkylated hydroxyph'en'ylFethers, can be dispersed in propylene glycol to givea concentrate whichishighly useful as an antioxidant for fats and oils. Advantageously, thetotalweight of the alkylated hydroxyphenyl ether the concentrate is'from10 to 60%of the total'wei'ght of the concentrate. The remainder cari'bepropylene glycol alone, or propylene glycol plusanjadditionalantioxidant; e. g. 'a p-dihydric phenol, e. gm-hydroquinonefl'toluliydroquinone, 'ethylhydroqu none, 'n-propylliydroguinone;rgbutylhydroqui none, tertL: butylhydroquinone, etc. ;-or propylene 8Claims. (01. 252 404i glycol plus at least one synergizing acid, orpropylene glycol plus the additional antioxidant plus at least onesynergizing acid. Most advantageously, the total weight of the alkylatedhydroxyphenyl ether in the concentrate is from l5 to 50% of the totalweight of the concentrate.

When employed, the weight of the p-dihydric phenol is advantageouslyfrom 5 to 20% of the total weight of the concentrate. Where at least onesynergizing acid is employed, the total weight of the synergizing acidis advantageously from 3 to 10% of the total weight of the concentrate.In no case, should the weight of propylene glycol be less than from 40to 70% of the total weight of the concentrate.

Advantageously, the total weight of the alkylated hydroxyphenyl' etheremployed is from .1375 to 2.25 times the total weight of the p-dihydricphenol. Advantageously, the total weight of the synergizing acid is from0.3 to 0.7 times the total weight of the p-dihydric phenol.

The alkylated hydroxyphenyl ethers which I employ in practicing myinvention can be represented by the following general formula:

' wherein R1 represents an alkyl group containing from 1 to 2 carbonatoms, and R2 represents a tertiary alkyl group containing from 4 to 5carbon atoms. Typical examples are: 2-tert. butyl- 4-hydroxyanisole,3-tert. butyl-l-hydroxyanisole, 2-tert. butyl-4-hydroxypheneto1e,3-tert.- butyl- 4-hydroxyphenetole, B-tert. amyl-4-hydroxyanisole,3-tert. amyl-i-hydroxyphenetole, etc.

Among the synergizing acids which I employ are citric acid,orthophosphoric acid, metaphosphoric acid, tartaricacid, ascorbic acid,etc.

An efiicacious concentrate which can be prepared according to myinvention is represented by the following example:

Such a concentrate is of such composition that one pound is sufiicientto stabilize one ton of lard. Such a concentrate is a homogeneous systemeven at temperatures as low as 20 C. It is, therefore, capable of beingmanufactured and handled in ordinary channels of commerce withoutseparation of' the added components. Propylene glycol issatisfactory forincorporation in edible products in concentrations much greater thanresult from use of this mixture. In contrast thereto, a material such asglycerin will not function in.

a satisfactory manner because of the difiiculty of getting the abovetype compounds to disperse therein and like disadvantages.

In contrast to the fats stabilized against oxidative rancidity withhydroquinone without the use of propylene glycol as a dispersing medium,fats stabilized according to the method set forth in the above examplecontained the antioxidant uniformly dispersed throughout the entire bodyof the fat, thus enabling the fatty material to be stored for longerperiods of time, and also to be further processed (as, for example,bycooking,

' etc.) without removal of the antioxidant, to give products which arealso stable to the influences ofoxidative' rancidity.

Althoughthe above exampleillustrates a composition containinghydroquinone, an alkylated hydroxyphenyl ether and a synergizingacid, my

invention also contemplates a concentrate of butylated hydroxyanisole inpropylene glycol,

-'butylated hydroxyphenetole in propylene glycol, jZ-tertiaryamyl--hydroxyanisole in propylene glycol, 3-tertiaryamyl-4-hydroxyanisole in'proplyene glycol,

Z-tertiary amyl-4-hydroxyphenetole in propylene glycol, 3-tertiaryamyl-4- hydroxyphenetole in propylene glycol, or mixtures of oneor more(e. g. 1 to 3) of these alkylated hydroxyphenyl ethers with a p-dihydricphenol, or with at least one (e. g. 1 to 2) synergizq ing acid, such ascitric acid, ortho-phosphoric acid, metaphosphoric acid, ascorbic acid,tartaric acid, etc., or with -p-dihydric phenol plus at least 'one ofsaid synergizing acids. 7

Moreover, in the above example, the citricacid can be replaced by 6parts by weight of ascorbic acid, tartaric acid, metaphosphoric acid ororthophosphoric acid. Still other compositions which can be used are,for example, the following:

Other fats or fatty materials, such as the glycerides of fatty acids,peanut oil,. palm oil, cocoanut oil, cottonseed oil, soya bean oil,sunflowerseedoiLsesame oil, shortenings (especially those of thedryplastic type), ,fat-oil mixtures,

;etc. can be stabilized by ,dispersing therein,one of my concentrates inpropylene glycol. The butylated hydroxyanisole of theaboveex '4 amplesis a mixture of about equal parts by weight of:

OCH: 0 OH:

CCHa CH:

3-tert. butyl-4-hydroxyanisole Z-tert. butyl-4-hydroxyanisolc Instead ofa mixture of S-tert. butyli-hydroxyanisole and 2-tert.butyl-4-hydroxyanisole, like parts by weight of either of the compoundscan be used in the above examples. The butylated hydroxyanisoles can bereplaced with either 2- tert. butyl-4-hydroxyphenetole or 3-tert. butylY -4-hydfoxyphenetole or a mixture thereof, or by Z-tert.amyl-4-hydroxyanisole or 3-tert. amyl-4- hydroxyanisole or 2-tert.amyl-l-hydroxyphenetole or 3-tert. amyl-l-hydroxyphenetole or a mixtureof such tertiary amyl compounds.

By the termfpropylene glycol, I mean the compound which has thefollowing formula:

The alkylated hydroxyphenyl others can be prepared by reactingp-hydroxyanisole or p-hydroxyphenetolewith tert. butyl or tert. amyl a1-the presence of orthophosphoric acid as a catcohol, at. a temperature offrom to C., in

alyst. The alkylated hydroxyphenyl ethers can also be prepared byreacting p-hydroxyanisole or p-hydroxyphenetole with isobutylene or withisoamylenein'the presence of sulfuric acid.

What I claim asmy invention and desire to be secured by Letters Patentof the United States is:

l. A concentrate, containing. propylene. glycol and at least one'alkylated hydroxyphenyl ether selected from the group consisting ofthose represented by the following. general formula:

I OH.

wherein R1 represents an alkyl group containing from 1 to 2 carbonatomsand R2 representsa tertiary-alkyl group containing from 4 to 5carbon atoms,- the total weight of the alkylated total weight of theconcentrate.

2. A concentrate containing propylene glycol, a p -dihydric phenol andat least one alkylated hydroxyphenyl ether selected from the groupconsisting of those represented 'by'the following general formula:

' hydroxyphenyl ether being fromlO to 60% of the wherem'glirepresentsIanm l oup containing fl' s r natomsaan R2 represents'a r -m a k oup "con aing from 4-,. to, 5 carbon-M91118, the t awei nt ofthe alkylated y nylhr .being from 10, to 166%, ;of

M Weight of he..z n ntrate,' "and: the wei tthe n-q h iah nol-be.mg,rrom

, '5 i 31 1 t t tala gis tbr e concentrate,

.5 the weight of the propylene glycol being from 40 to 70% of the totalweight of the concentrate.

3. A concentrate containing propylene glycol, hydroquinone, at least onealkylated hydroxyphenyl ether selected from the group consisting ofthose represented by the following general formula:

wherein R1 represents an alkyl group containing from 1 to 2 carbon atomsand R2 represents a tertiary alkyl group containing from 4 to 5 carbonatoms, and at least one synergizing acid selected from the groupconsisting of citric acid, orthophosphoric acid, metaphosphoric acid,tartaric acid and ascorbic acid, the total weight of the alkylatedhydroxyphenyl ether being from to 60% by weight of the total weight ofthe concentrate, the total weight of the hydroquinone being from to 30%of the total weight of the concentrate, the total weight of thesynergizing acid being from 3 to 10% of the total weight of theconcentrate, and the weight of the propylene glycol being from 40 to 70%of the total weight of the concentrate.

4. A concentrate containing propylene glycol, a mixture of Z-tert.butyl-4-hydroxyanisole and 3 tert. butyl-4-hydroxyanisole, hydroquinoneand citric acid, the weight of the mixture of 2- tert.butyl-4-hydroxyanisole and 3-tert. butyl-4- hydroxyanisole being from 10to 60% of the total weight of the concentrate, the weight ofhydroquinone being from 15 to 30% of the total weight of theconcentrate, the weight of the citric acid being from 3 to 10% of thetotal weight of the concentrate, and the weight of the propylene glycolbeing from 40 to 70% of the total weight of the concentrate.

5. A concentrate containing propylene glycol, a mixture of 2-tert.butyl-4-hydroxyanisole and 3 tert. butyl-4-hydroxyanisole, hydroquinoneand citric acid, the weight of the mixture of 2- tert.butyl-4-hydroxyanisole and 3-tert. butyl-4- hydroxyanisole being from 10to 60% of the total weight of the concentrate, the weight of thehydroquinone being from 15 to 30% of the total weight oi! theconcentrate, the weight of the and 3-tert. butyl-4-hydroxyanisole 30Hydroquinone 15 Citric acid 6 7. A concentrate having the followingcomposition:

Parts by weight Propylene glycol Mixture of 2-tert.butyl-4-hydroxyanisole and 3-tert. butyl-4-hydroxyanisole 100 8. Aconcentrate having the following composition:

Parts by weight Propylene glycol 100 Mixture of 2-tert.butyl-4-hydroxyanisole and 3-tert. butyl-4-hydroxyanisole HydroquinoneJAMES E. MAGOFFIN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,104,084 Latham Jan. 4, 19382,115,040 Nitardy Apr. 26, 1938 2,310,710 Rosenwald Feb. 9, 19432,333,657 Mattill et a1. Nov. 9, 1943 2,500,543 Hall Mar. 14, 19502,521,856 Kraybill et a1 Sept. 12, 1950 OTHER REFERENCES Boehm et al.,in Quart Journal of Pharm., vol. 16 (1943), pp. 232-43.

Gregory, Uses and Applications of Chemicals and Related Materials," vol.II, p. 2'75, Reinhold Pub. Corp. N. Y. 0., N. Y., 1944.

1. A CONCENTRATE CONTAINING PROPYLENE GLYCOL AND AT LEAST ONE ALKYLATEDHYDROXYPHENYL ETHER SELECTED FROM THE GROUP CONSISTING OF THOSEREPRESENTED BY THE FOLLOWING GENERAL FORMULA: